Metallurgical furnace.



PATENTED MAY 29, 1906.

I. L. EGBERTS.

APPLICATION FILED MAY 31. 1904.

METALLURGICAL FURNAGE.

'UNITED STATES PATENT OFFICE.'

ISAIAH L. ROBERTS, OF NEW YORK, N. Y., ASSIGNOR OF ONE-HALF TO Y JAMES TURNER MOREHEAD, OF NEW YORK, Y.

METALLURGIGAL FURNACE.

Specification of Letters Patent.

Patented May 29, 1906.

i Application led May 31,1904. Serial No. 210,394.

To all whom it may concern:

Beit known that I, IsAIAH L. ROBERTS, a citizen of the United States, residing at New York, county of Kings, and State of New York, have invented" certain new and useful Improvements in Metallurgical Furnaces, of whichthe followin is a specification, reference being had to t e drawings accompanying and forming part of the same.

My invention relates to that type of furnace for metallurgical and other purposes in which the containing vessel is heated by the electric current, but pertains more particularly to the heating of a vessel of conducting material, such as iron. Heretofore it has been common to heat such pots or vessels and other materials or articles by passin current through resistances located aroun them, also by insulated conductors vin proximity to them. In my invention, however, the conducting vessel or other material is placed in contact with the resistance and is made one of the electrodes or terminal connectors thr ugh which the current is delivered to the eslstance, or at least a part of the circuit. By this arrangement I find that the heating of the vessel is effected more readily and economically than in the case of any of the previous methods with which I am familiar.

The invention itself consists in the novel features, combinations of elements, and arrangements of parts hereinafter described, and more particularly pointed out in the claims.

The preferred embodiment is typically illustrated in the accompanying drawings, in which- Figure 1 is a plan view. Fig. 2 is a central longitudinal section of Fig.` 1, and Fig. 3 a similar section of a modification.

The furnace is inclosed in a receptacle or jacket A, preferably of iron, lined with heatinsulating material B of any suitable character, asa mixture of asbestos and magnesium carbonate, ground together and well packed in place. Within the latter is a chamber of refractory material C, such. as fire-brick, within which is supported a crucible or other vessel D, of conducting material. Between the walls of the chamber and the vessel is a mass of resistance material E. I have shown it onl on two sides of the vessel inFigs. 1 and 2 an only at' the bottom in Fig. 3. As the v rial.

resistance material I prefer to use ganulated or powdered coke. In contact wit the coke are terminal or electrode plates F F, through V which current is delivered to the resistance. From the arrangement in Figs. 1 and 2 it will be seen that the conducting vessel forms part of the circuit, serving to connect the two masses of carbon. The carbon may be screened from the air by covers H, of brick or other material, if desired. In the bottomA of the crucible is an outlet G, providedwith a cock G', by which the contents may be drawn off at will without removin the vessel. By making the walls of the ischargeopening very massive a considerable amount f of heat is retained therein, preventing the cooling of the material in the same; otherwise the cooled material might obstruct the passage.

In the modification shown in Fig. 3 the crucible rests on the layer of resistance material E, the latter being in contact with the electrode or terminal' F. The crucible D constitutes the other terminal, and to deliver current thereto it is provided with a removable cover I, carrying the lead K. The latter may be secured to a heavy conductin block J, which merely rests on vthe lid. n this construction the crucible is adapted to be removed bodily, and to permit ready grasping of the same by the-tongs or other evices the walls C may be recessed at the edges C', as shown.

From the foregoing the operation ofthe furnace will be readily understood. The resistance material is heated by the current,

the quantity of heat evolved being dependent upon the usual factors. If it is desired to increase the resistance, sand, magnesia, or lime may be mixed with the carbon 1n the desired proportions.

The chief advantage of my invention resides in the better distribution of the heat. This is due to the better distribution of the current resulting from the large area of contact of the crucible and the resistance mate- The greater part of the current traverses the lower parts of the resistance material on account of the greater density of those parts; but as the material in the pot is of course in its bottom this concentration of the heat is in reality an advantage. In the form shown in Fig. 3 the concentration of .the heat will generally occur near the center IOO of the resistance material where it is in con tact With the pot.

The forms described are of course mereljr typical of the invention, which may be Variously embodied Without departure from its proper scope.

What I claim isl. In a furnace of the kind described, the combination of a chamber, a vessel of conducting material in the chamber, a mass of resistance material in contact with the vessel, an electrode in electrical connection With the said mass, and a second electrode electrically disconnected With the said mass save' through the said conducting VesselJ as set forth. f

2.v In a furnace of the'kind described7 the' combination of a conducting Vessel, massesof resistance material on opposite sides of thel senseo contact "with each' other, and electrodes connected With the said masses of resistancev materiai, as set forth.

ISAAH L. RBERTS. Witnesses M. Lawson Dyna, S. S'. DUNHAM. 

